Ping flooding

Jerry Anderson jerry at
Thu Jul 11 17:17:39 UTC 1996

> That's once again a matter of defaults -- routers should _by
> default_  discard all packets from interfaces which they won't
> use for forwarding those packets back.

This is a sweeping statement.  I'm not sure we should buy into it
without thinking about it pretty hard.  However, I am no routing
theorist, so maybe this has already been thoroughly explored by
the high-level networking gurus.

I see three obvious advantages:

    1.  Prevention of IP spoofing.
    2.  Prevention of asymmetric routing.
    3.  Better TCP windowing and better performance when all
        packets follow the same path.

However, are the benefits worth the overhead?  What are the
effects on network redundancy?  What other issues am I

Jerry Anderson                                       jerry at
Principal Engineer                                 (402) 436-3030
Implementation & Consulting     
   Global Internet Network Services (formerly known as MIDnet)

More information about the NANOG mailing list